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Combined Bending and Tension.

453

A =

48El   -d-T-^

_8/"M
~~TT

A =

and

8000 x/2

__                          -     ...... _   _____

48 A /El     6^E          1000     6 x 28,000,000 #

/_ 6 x 28,000,000 _ 2 1
h     8000x1000       i

Combined Bending andjjTension Stress- Action. 

Let the bracket in Fig. 412 support a weight W.    There are two

actions upon the section : bending due to moment W r, and ten-
sion by direct load W.    Then

Wr

( i ) Bending action :   W r =/0 Z an d f0 =  -

or

Wr

Wr

W
(2) Tensile Action :   W**fta and/t = 

W   Wr

.:  Maximum tensile stress (on inner edge of bK) = Ft =  + -^

O=i  for  H   and  T sections, and  OiJ or 2 for solid
sections.    (Seep. 436.)

Strength of Crane Hooks.  In these, theory and practice
are considerably at variance.    The following table is regularly